Guy qualified from Cambridge University and the United Medical and Dental schools of Guy’s and St Thomas’ and trained in Infectious Diseases and Microbiology in Brighton, the Oxford University Clinical Research Unit (OUCRU) in Vietnam, Imperial College London, and the Hospital for Tropical Diseases in London. His research interests focus on improving the diagnosis and treatment of severe bacterial infections, including tuberculosis. He has been Director of OUCRU, a Wellcome Trust funded Africa Asia Programme, since 2013. Guy became a Fellow of the UK Academy of Medical Sciences in 2018, and he was awarded an MBE in the 2021 Queen’s Birthday Honours for services to public health and Vietnam-UK relations.